1. Field of the Invention
The present invention generally relates to computer-telephone integrated systems, and more particularly to a computer-telephone integrated system in which a telephone switching service request part makes a switching control request with respect to a switch engine which has a function of switching via a service request process/call information notifying means, and the switching engine makes a call process. The present invention also relates to a switching control apparatus adapted to the computer-telephone integrated system, and to a computer-readable storage medium which stores a program for causing a computer to realize the functions of the switching control apparatus.
2. Description of the Related Art
Conventionally, computers such as personal computers employ a call connection control system which makes a switching control request with respect to a switch engine having a switching function, by use of an Application Programmatic Interface (API), and makes a call process of a telephone switching by the switch engine. A Telephony Services Application Programmatic Interface (TSAPI) is a typical example of the API.
The TSAPI uses a call model of the telephone switching shown in FIG. 1. When making a connection by the telephone switching, a device 33 and a switching system (not shown) are connected by a connection 31, and the switching system and a device 34 are connected by a connection 32. A call 30 is completed by connecting the two connections 31 and 32 by the switching system, so as to enable a service. FIG. 1 shows the call model in this state where the service is possible.
According to this call model shown in FIG. 1, one call 30 requires the two connections 31 and 32. In other words, the call is based on two connections, and two connections are necessary in order to complete one call. When representing a state where only one device participates, such as when making a call out, a dummy device and a dummy connection are required. Hence, when a call control is carried out in this call model, call information is managed by the connections 31 and 32 which are identified by a combination of a device identifier and a call identifier and describe the relationships of the devices 33 and 34 and the call 30. The TSAPI uses the above described call model to carry out the call control and the call management.
FIG. 2 is a diagram for explaining connection states of the TSAPI. The connection states of the TSAPI include a null state, a connected state, an initiated state, an alerting state, a fail state, a hold state and a queued state.
The null state refers to a state where the call and the device are not connected, physically or logically.
The connected state refers to a state where the call and the device are connected both physically and logically. In a case where the device makes originates a call, the connected state refers to a state where a transmission procedure with respect to a destination is completed. On the other hand, in a case where the device makes a call reception, the connected state refers to a state where a response is returned with respect to the calling.
The initiated state refers to a state where the switching system urges a user to carry out the procedure necessary for the call origination.
The alerting state refers to a state where the call is calling the device, and includes three modes, namely, a ringing mode, an offered mode and an entering distribution mode. The ringing mode refers to a mode in which a normal device is being called. This normal device excludes offered devices such as a device which transfers the call, and distribution devices such as a key number telephone which distributes the call. The offered mode refers to a mode in which the call is received by an offered device and an instruction such as where the call is to be transferred is waited with respect to the received call. The entering distribution mode refers to a mode in which the call is received by a distribution device.
The fail state refers to a state where a normal state transition of the connection failed for some reason.
The hold state refers to a state where the call and the device are logically connected, but are not physically connected.
The queued state refers to a state where the occurrence of some kind of a state change or an action is waited.
FIG. 3 is a diagram showing state transitions among the connection states of the TSAPI shown in FIG. 2.
Next, a description will be given of the hold state of the call model shown in FIG. 1, by referring to FIG. 4. In FIG. 4, it is assumed for the sake of convenience that a service is being provided between a device D1 and a device D2, and a device is on hold. In this case, the devices D1 and D2 are in the connected state, and the call and the devices D1 and D2 are both physically and logically connected.
On the other hand, since the device D3 is on hold, the call has acquired a line, but a communication circuit of the device D3 is disconnected from the line. Hence, the call exists with respect to the device D3, and the call and the device D3 are logically connected. However, because the communication circuit of the device D3 is disconnected from the line, the device D3 is physically disconnected from the device D1, and no service can be provided between the devices D1 and D3. In this case, although the device D3 on hold is physically disconnected from the device D1, the device D3 by itself cannot exist in the call model because the call exists with respect to the device D3.
According to the conventional call information management, the call and the device are connected, and it is impossible to manage only the device by disconnecting the device, as may be seen from the hold state described above. In addition, since the call is based on two connections, and two connections are necessary in order to complete one call as described above, it is impossible for only one device to exist in the call model. As a result, there is a problem in that it is impossible to request from the application a control in units of devices, such as controlling the call reception or the call origination of a trunk.
Accordingly, it is a general object of the present invention to provide a novel and useful computer-telephone integrated system, switching control apparatus and computer-readable storage medium, in which the problem described above is eliminated.
Another and more specific object of the present invention is to provide a computer-telephone integrated system, a switching control apparatus and a computer-readable storage medium which enable control in units of devices, by making a path connection state independent when a Computer Telephony Integration (CTI) application, which is a telephone switching service request part, when controlling a call of a switch engine.
Still another object of the present invention is to provide a computer-telephone integrated system comprising a switch engine carrying out a switching control, devices coupled to the switch engine, a service request part requesting a telephone switching service with respect to the switch engine, and service request process/call information notifying means providing an interface function between the switch engine and the service request part, where the service request process/call information notifying means processes a switching service request from the service request part to the switch engine, and notifies call information related to the devices and the switch engine from the switching engine to the service request part, and the call information includes information related to states of the devices and information related to a connection of a path between the switch engine and the devices. According to the computer-telephone integrated system of the present invention, the call information management by the service request process/call information notifying means is made using the two kinds of information. Hence, it is possible to carry out a control in units of devices, independently of the connected state of the path, when controlling the call in response to a request from the service request part.
A further object of the present invention is to provide the computer-telephone integrated system described above, wherein a connection between a first one of the devices and the switch engine is established independently of a connection of a path between a second one of the devices and the switch engine, and a service is provided in units of the first device having an established connection with the switch engine, based on a service request from the service request part. According to the computer-telephone integrated system of the present invention, the connection between one device and the switch engine can be established independently of the connection of the path between the switch engine and another device. As a result, it is possible to provide a service in units of the one device having the established connection to the switch engine, thereby enabling a one-directional connection such as driving a talkie apparatus.
Another object of the present invention is to provide the computer-telephone integrated system described above, wherein a path between two devices is connected based on a service request from the service request part when the switch engine is called from the two devices. According to the computer-telephone integrated system of the present invention, it is possible to provide a service between two devices by connecting the path between the two devices when the switch engine is called from the two devices.
Still another object of the present invention is to provide the computer-telephone integrated system described above, wherein the switch engine originates a call to a first one of the devices based on a service request from the service request part when the switch engine is called from a second one of the device, so as to connect a path between the first device and the second device. According to the computer-telephone integrated system of the present invention, it is possible to connect two devices via the switch engine when one of the two devices calls the other of the two devices. In other words, when one device dials the other device, the switch engine is called. Then, the switch engine originates a call to the other device and calls the other device. The two devices are connected by the switch engine when a response is received from the other device.
A further object of the present invention is to provide the computer-telephone integrated system described above, wherein when the switch engine is called from a first one of the devices after originating a call from the switch engine to a second one of the devices and establishing a connection between the switch engine and the second device, the switch engine connects a path between the first device and the second device based on a service request from the service request part. According to the computer-telephone integrated system of the present invention, it is possible to provide a guidance service by making the second device a guidance apparatus, and making the first device a guidance listener.
Another object of the present invention is to provide the computer-telephone integrated system described above, wherein the switch engine independently originates a call to two of the devices based on a service request from the service request part, and connects a path between the two devices. According to the computer-telephone integrated system of the present invention, it is possible to make an accounting to a company with respect to a call which is made between a customer""s telephone and a company employee""s home telephone, for example.
Still another object of the present invention is to provide the computer-telephone integrated system described above, wherein after establishing a connection between a first one of the devices and the switch engine, the switch engine simultaneously originates a call to the devices based on a service request from the service request part and connects a path between the first device and one of the devices which responds, so as to provide a broadcast service. According to the computer-telephone integrated system of the present invention, it is possible to provide a broadcast service.
A further object of the present invention is to provide the computer-telephone integrated system described above, wherein, in a state where a connection between the switch engine and three or more of the devices is established and a path is connected between first and second devices among the three or more devices, the switch engine releases the path between the first and second devices based on a service request from the service request part, and switches a connection of a path by connecting a path between one of the first and second devices and a third device having an established connection to the switch engine. According to the computer-telephone integrated system of the present invention, it is possible to freely switch the device to which the call is established.
Another object of the present invention is to provide the computer-telephone integrated system described above, wherein the switch engine carries out a conference based on a service request from the service request part by originating a call to and connecting to a first one of the devices which is to make the conference, connecting a second one of the devices which is to participate in the conference to the switch engine by originating a call from the switch engine to the second device or by being called from the second device, and connecting a path between the first device and the second device. According to the computer-telephone integrated system of the present invention, it is possible to provide a conferencing service.
Still another object of the present invention is to provide a computer-readable storage medium which stores a program for causing a computer to carry out a switching control, comprising first means for causing the computer to process a service request from a service request part requesting a telephone switching service with respect to a switch engine which carries out a switching control, and second means for causing the computer to notifying, to the service request part, information related to states of devices coupled to the switch engine and information related to a connection of a path between the switch engine and the devices. According to the storage medium of the present invention, it is possible to realize switching functions by a computer which executes the program stored in the storage medium.
A further object of the present invention is to provide the computer-readable storage medium described above, wherein the first means includes means for causing the computer to originate a call to the devices, means for causing the computer to release a connection between the switch engine and the devices, means for causing the computer to connect a path between two of the devices, and means for causing the computer to release a connection of a path between two of the devices. According to the storage medium of the present invention, it is possible to process various kinds of request from the service request part by the computer which executes the program stored in the storage medium.
Another object of the present invention is to provide a switching control apparatus comprising a switch engine carrying out a switching control, a service request part requesting a telephone switching service with respect to the switch engine, and service request process/call information notifying means providing an interface function between the switch engine and the service request part, wherein the service request process/call information notifying means processes a switching service request from the service request part to the switch engine, and notifies call information related to devices and the switch engine from the switching engine to the service request part, and the call information includes information related to states of the devices and information related to a connection of a path between the switch engine and the devices. According to the switching control apparatus of the present invention, the call information management by the service request process/call information notifying means is made using the two kinds of information. Hence, it is possible to carry out a control in units of devices, independently of the connected state of the path, when controlling the call in response to a request from the service request part.
Other objects and further features of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.